Bumper with face-mounted reinforcer

Abstract

A bumper includes a tubular primary beam, such as a rollformed D-shaped beam made of high-strength steel, with at least one longitudinal channel formed in its face surface. One or more mild steel thin-wall tube sections are positioned in the channel(s) and welded in place for increased strength in selected areas, while permitting overall weight savings in the bumper.

1 . A bumper comprising: 
 a bumper beam having a length and a primary impact surface with at least one longitudinal channel formed therein; and    a tubular reinforcer positioned at least partially in the channel and secured to the bumper beam.    
   
   
       2 . The bumper defined in  claim 1 , wherein the bumper beam is made of a first metal and the tubular reinforcer is made of a second metal that is lower in tensile strength than the first metal.  
   
   
       3 . The bumper defined in clam  2 , wherein the bumper beam is tubular.  
   
   
       4 . The bumper defined in  claim 1 , wherein the primary impact surface is curved longitudinally, and the tubular reinforcer has a similar longitudinal curvature.  
   
   
       5 . The bumper defined in  claim 1 , wherein the tubular reinforcer extends a distance less than half of the length of the primary impact surface.  
   
   
       6 . The bumper defined in  claim 1 , wherein the channel has a cross section that includes an arcuate section, and the cross section of the tubular reinforcer has a mating arcuate shape.  
   
   
       7 . The bumper defined in  claim 1 , wherein the primary impact surface includes a second channel that extends parallel the first-mentioned channel, and including a second tubular reinforcer that is positioned at least partially in the second channel and that extends parallel the first-mentioned tubular reinforcer.  
   
   
       8 . A bumper comprising: 
 a tubular beam having a length and an outer wall, the outer wall having a primary impact surface with at least one longitudinal channel formed therein; and    an elongated reinforcer positioned at least partially in the channel and secured to the beam.    
   
   
       9 . A bumper comprising: 
 a beam having an outer wall defining a first curvature; and    at least one reinforcer having a second curvature different from the first curvature when in an unstressed state, but which is resiliently flexed to a stressed state to match the first curvature and which is attached to the outer wall to reinforce the beam.    
   
   
       10 . The bumper defined in  claim 9 , wherein the beam is tubular.  
   
   
       11 . The bumper defined in  claim 9 , wherein the reinforcer is tubular.